Epidemiological characteristics and spatio-temporal analysis of influenza in Sichuan Province from 2015 to 2024

Utilising influenza monitoring data from Sichuan Province, descriptive research and geographic information systems (GIS) were employed to examine the epidemiological features and spatiotemporal patterns of influenza in the province from 2015 to 2024. From 2015 to 2024, Sichuan Province reported a total of 2,105,900 influenza cases, exhibiting a general rising trend in incidence, notably marked by high rises in 2019 and 2023. Global geographic autocorrelation study indicated substantial positive spatial autocorrelation in influenza incidence from 2019 to 2024 (Moran's I > 0, P < 0.05). Local spatial autocorrelation study identified clustering patterns throughout Sichuan Province, with high-high clustering mostly in the centre region and low-low clustering mainly in the western and eastern parts. Hotspot study indicated a progressive rise in the quantity of influenza hotspots, predominantly located in the central region, namely within urban areas of the plains. Analysis of the standard deviational ellipse of the movement trajectory of influenza outbreak centres indicated a shift in influenza transmission within the province from central urban areas to the southern regions, accompanied by a gradual dissemination. Our findings demonstrate that influenza prevention and control continues to be a significant public health concern in Sichuan Province. Region-specific influenza prevention and control strategies must be formulated, emphasising enhanced surveillance of low-incidence influenza clusters and preferential resource allocation to areas with elevated influenza incidence, to effectively address potential future influenza pandemics and mitigate the influenza burden.